槽式DSG太阳能热发电集热管传热特性探讨

本文运用能量守恒的方法建立了集热管一维模型,分析了集热管在不同工况下的集热效率,同时建立二维模型给出了集热管出口温度和出口干度的计算方法,分析了24米长集热管在不同工况下的出口温度和干度,为今后建立槽式DSG太阳能热集热发电站提供参考意见。     

10Gbit/s高T0无制冷分布反馈激光器

与折射率耦合分布的分布反馈（DFB）激光器相比,不管界面反射率是多少,增益耦合DFB激光器都能稳定地单纵模工作,而且具有高速、低啁啾的特性．本课题组用AlGaInAs/InP材料,采用增益耦合DFB结构,进行了单纵模激光器研发,并对器件特性进行了测试分析．     

Rate adaptive resource allocation in orthogonal frequency division multiple access system using multi‐objective immune algorithm

Rate adaptive downlink resource allocation in orthogonal frequency division multiple access system is a constraint optimization problem, which is to maximize the minimum data rate of the user subject to constraint that total power cannot exceed a given value. How to handle the constraint is a key issue for constrained optimization problem. Different with the available schemes on constraint handling, the proposed algorithm converts the constraint into an objective. Then, the resource allocation is combined into a multi‐objective optimization problem. An improved multi‐objective optimization algorithm based on artificial immune system is proposed to solve it. The simulation results show that, compared with previous schemes, the proposed algorithm performs remarkable improvement in sum capacity. Copyright © 2013 John Wiley & Sons, Ltd.     

DATA PREPROCESSING AND RE KERNEL CLUSTERING FOR LETTER

Many classifiers and methods are proposed to deal with letter recognition problem. Among them, clustering is a widely used method. But only one time for clustering is not adequately. Here, we adopt data preprocessing and a re kernel clustering method to tackle the letter recognition problem. In order to validate effectiveness and efficiency of proposed method, we introduce re kernel clustering into Kernel Nearest Neighbor classification （KNN）, Radial Basis Function Neural Network （RBFNN）, and Support Vector Machine （SVM）. Furthermore, we compare the difference between re kernel clustering and one time kernel clustering which is denoted as kernel clustering for short. Experimental results validate that re kernel clustering forms fewer and more feasible kernels and attain higher classification accuracy.     

基于EIB的融合组网技术在智能家居中的应用

介绍智能家居系统中的常用组网技术,分析智能家居系统的实际需求,然后结合各类组网技术的适用性,提出一种以EIB为基础,同时融合IrDA和Wi-Fi技术的智能家居系统组网技术,并在上海市长宁区某街道的一个智能家居体验点中进行应用。该组网技术兼顾满足了智能家居系统高可靠性、高稳定性以及高速性的需求,具有一定的应用前景。     

基于临近空间飞行器的区域自组网优化部署算法

该文针对基于临近空间飞行器的新型区域自组织网络,提出一种优化部署方案。采用线性递减权值粒子群算法,对于临近空间飞行器节点,一个粒子代表所有飞行器节点坐标集合,以最大化网络覆盖空间的联合通信覆盖率为目标,进行节点的优化部署。对于地面骨干节点,一个粒子代表一个网络分区内骨干节点坐标,以最多覆盖节点数和最小平均跳数为目标,进行初始化。网络运行过程中根据任务区域内数据业务分布情况,以趋近数据量多、业务优先级高的区域为目标,动态调整更新地面骨干节点位置。仿真结果表明,所提方案能为上层协议的运行提供良好基础,使网络分组投递率、延迟和开销等性能得到改善。     

2.4GHz产品巴西Anatel认证的RF要求

详细介绍了巴西Anatel认证RF测试部分对于蓝牙和Wi-Fi 802.11b＋g产品的要求和测试方法,并对于各个测试项目在实际测试中需要注意的问题进行解析,最后分析了相关通用国际标准在认证中的适用性。     

Surface shape control of the workpiece in a double-spindle triple-workstation wafer grinder

Double-spindle triple-workstation(DSTW) ultra precision grinders are mainly used in production lines for manufacturing and back thinning large diameter(≥300 mm) silicon wafers for integrated circuits.It is important, but insufficiently studied,to control the wafer shape ground on a DSTW grinder by adjusting the inclination angles of the spindles and work tables.In this paper,the requirements of the inclination angle adjustment of the grinding spindles and work tables in DSTW wafer grinders are analyzed.A reasonable configuration of the grinding spindles and work tables in DSTW wafer grinders are proposed.Based on the proposed configuration,an adjustment method of the inclination angle of grinding spindles and work tables for DSTW wafer grinders is put forward. The mathematical models of wafer shape with the adjustment amount of inclination angles for both fine and rough grinding spindles are derived.The proposed grinder configuration and adjustment method will provide helpful instruction for DSTW wafer grinder design.     

Property comparison of polarons in zinc-blende and wurtzite GaN/AlN quantum wells

The properties of polarons in zinc-blende and wurtzite GaN/AlN quantum wells with Fr(o|¨)hlich interaction Hamiltonians are compared in detail.The energy shifts of polarons at ground state due to the interface(IF), confined(CO) and half-space phonon modes are calculated by a finite-difference computation combined with a modified LLP variational method.It is found that the two Fr(o|¨)hlich interaction Hamiltonians are consistent with each other when the anisotropic effect from the z-direction and the x-y plane is neglected.The influence of the anisotropy on the polaron energy shifts due to the IF phonon modes for a smaller well width or due to the CO phonon modes for a moderate well width is obvious.In addition,the built-in electric field has a remarkable effect on the polaron energy shifts contributed by the various phonon modes.